I went to Windsor Canada since I live close by to get the Sceptor fuel cans. Since they had one I picked up a water can too. Soo much better quality plastic and seals then the Front Runner stuff. I laid both the gas and water cans flat in a trunk to test them and they don't leak a drop. The Sceptor cans would be totally suited to pressurizing with a pick up hose and having the cans dispense water that way. The design is good but for quality and price the Sceptor water jug is the way to go and modify it with a spigot if you want.
I have been using this method for awhile now. Works perfectly. The cans mentioned by the original poster have alot of problems:
They leak from the top
Have to instantly modify them for a better faucet
The faucet in the bottom can easily break, or open when stored or jostled while driving
They have a small fill opening; makes it harder to get in there and scrub them out. The scepter cans have a huge fill cap
Overall the frontrunner cans are advert hype and not made for true long term use.
Perhaps best suited for the weekend warrior?